The cyclotides are potent insecticides inhibiting the growth of insect larvae

This site is dedicated to the study of a fascinating new
class of plant proteins called the Cyclotides. These recently
characterised molecules found in plants of the Rubiaceae
and Violaceae families are small disulfide-rich proteins that
have the unusual feature of a cyclic backbone (hence the
name - cyclic peptides).
Apart from the cyclised backbone the cyclotides also
possess another unusual feature called a cystine knot.
This protein motif consists of three conserved disulfide
bonds two of which, along with their connecting backbone
segments, form an embedded ring in the structure that is
penetrated by the third disulfide bond. This combination
of cyclised backbone and cystine knot topology makes the
cyclotides a highly unusual and interesting class of protein.

Research in our lab is aimed at further characterising the cyclotides and adapting them for commercial and
medicinal use. Specific goals include: determining the role that cyclotides play in plants, discovering the
mechanism of action of the wide range of biological activities displayed by the cyclotides (including anti-HIV,
anti-bacterial and insecticidal activity), characterising the genetics of the cyclotides and further discovery of
novel cyclotides.

Cyclotides in the News

Cyclotides were recently the subject of the
Swiss Prot Protein Spotlight series - read the PDF file.

The structure of the trypsin inhibitor cyclotides was recently published in JBC and featured on the
cover.

Our review on circular proteins was recently featured on the cover of TiBS.